Electric telephone



(Nn Modal.)

' E. BERLINER.

Electric Telephon-e.

Patented Nov. 2, 1889.

s W M W i a, s 4 MM plate and the UNITED STATES PATENT EEICE.

EMILE BERLINER, OF BOSTON, MASSACHUSETTS.

, ELECTRIC TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 233.969, dated Novemner 2, 1880. Application filed September Il, i880. (No model.)

To all 'wh-0m, it muy concern.:

Be it known that I, EMILE BERLINER. a resident of Boston, county of Suffolk, State of Massachusetts, have invented a new and useful Improvement in Electric Telephones, which improvement is fully set forth in the following specification.

)Iy invention consists in a new and useful improvement in telephonie receivers for producing sound 'by means of varying electrical currents, of which the following is a specilication.

It is a fact and a scientific principle that if two electrodes be placed in contact to form partofa circuit and a current of electricity be passed through them a repulsion is exerted between them. Based on this fact I have constructed a simple receiver for an electric-telephone apparatus.

In Figure 2 ofthe drawings, A isa metal plate well fastened to the wooden box or frame, but able to vibrate. Againstthe plate and touching it is the metal ball c, terminating the rod B, which rests 0n the bar or stand d and presses against the plate, which pressure, however, can be regulated by the thumbscrew attached to the ball.

It' a current of electricity passes through the point ofcontact, or vice versa, a repulsive movement will take place between the plate and the ball,because both are charged with the same kind of electricity. This force of repulsion may be weakened or strengthened by varying the strength of the current. .as

that strength is varied byanyappropriatey form of electric speaking-telephone transmitter, (especially that shown at A ll of the variri ous ligures ofthe drawings, and more part-icularly described and claimed by me in another application tiled J une .4, 1877, of which thisis a division,) so will also the force of repulsion at the point in the receiver be alternately weakened and strengtl-iened as many times accordingly, and will therefore cause its plate to vibrate at the same rate and measure. The latter vibrations being communicated to the surrounding aix', the same kind of sound as uttered against the transmitter, Fig. l, will be reproduced at the receiver, F ig. 2, or in as many other receivi11g-instruments as are situated within the same electric circuit.

In Fig. 2 I have shown the receiver as` consisting ot'a diaphragm in contact with a ball. ln Figs. 3 and 4 I show it as somewhat ditl'erently mounted, and with the contact-piece in the form of a pin instead of a ball, and in Fig. 6 ina still diii'erent form with a carbon con` tact. In this gure, XV is a piece of carbon.

In Fig. 5 two platesin contact at their edges are shown.

In the drawings, the letter A represents a diaphragm or plate, preferably of thin metal oflimited conductive capacity, such as iron, steel, German silver, platinum, and also carbonsecnred in the frame m m in tlie box` f in any convenient manner.

The letter y representsaring resting against one side of said diaphragm, and capable of being made to bear upon the same with more or less force by means of set-screws a .in order that the tension ofthe diaphragm may be regulated.

lhe letter B represents a screw or piece of metal or carbon, pointed at one end and mounted in a cross-piece, 11,'in such position that the point will be in contact with the diaphragm A. The diaphragm A is connected with one pole of a battery by means of a wire, and thc pin or screw B with the other pole.

Fig. l shows the manner in which the complet-e apparatus, consisting of the transmitter A B and the receiver A B, is connected up in circuit.

It will be observed that the transmitter is ot' the same construction as the receiver. Xlhen asound is" uttered in the neighborhood of the transmitter its plate will vibrate accordingly, and the pressure between the plate and the pin or ball at the point of contact a will become weaker or stronger, according to the vibrations, and this variation of pressure will cause the current passing to become weaker or stronger, and thus effect the changes which operate the receiver,as already described.

As shown in Fig. 3, the boxj is provided with a tube, K, to which the ear of the operator may be applied in order to hear the sounds produced by the vibratory diaphragm whenthe instrument is employed as a receiver, and a tube, O, through which he can speak` when employing the instrument as atransmitter, so that the operator is not in need of Inoving the instrument or moving his head while carrying on a conversation. .This combination,

IOO

with the sound.- chamber of a telephone provided with the usual sound-passage or mouthpiece,nf an additional soundconveyer or hearing-tuhe'forms, however, no part of the inveution.

" I claim- 1. The herein-described method of producing social-vibrations in a plate by causing a varying electric current to pass to the plate, or to an elect rode connected therewith, from a second electrode in contact therewith, substantially as described.

2. An apparatus for producing sound hy means of a varying electric currcnt,\\'hich consists ot' a plate forming or carrying an electrode placed in contact with another electrode,

from one to the other of which thc electric current. is caused to pass.

3. An electric-telephone receiver to hepperat ed by varying electric currents, and 'consisting oi two contact-pieces within an electric circuit, one or hoth of which pieces consistof orare connected with avibratory diaphragm, whereby one electric current passing through said circuit exercisesa repulsion between said two electrodes corresponding to its strength, and thus produces corresponding motions in the diaphragm.

4. A system oftwo ormore telephone-instru. ments in electrical connection with each other, each consisting of two or more poles ot' an electrical circuit in contact. one with the other, either or both poles of each instrument being connected with a. vibratory plate, so that any vibration which is made at one contact is reproducedl at the other, substantially as set forth.

In testimony whereofv I have signed this specification in the presence of two suhscrihing witnesses.

EMILE BERLINER.

Witnesses:

C` H. GREAvEs, ALFRED J. MAYO. 

